I looked up what is the molecular formula for Phosphine and got this: PH3
Hope this helps! Let my know if this was correct.
Answer:
4) Van der waals forces
Explanation:
Krypton (Kr) belongs to the noble gas group and has fully filled valence orbitals. In the solid phase, Kr exists as a white solid with a face centered cubic structure.
Intermolecular forces of attraction from the strongest to the weakest include:
Ionic > hydrogen bonding > dipole-dipole > london dispersion
Kr is monoatomic and non-polar. When fully filled (stable) valence orbitals of 2 Kr atoms approach each other in close proximity they experience a repulsive force which prevents the formation of strong bonds. Thus, the only force of attraction in Kr is the long range weak Van Der Waals force also known as the london dispersion force.
The process through which Polonium is most likely to become stable is: B. alpha decay.
An unstable element refers to a chemical element that lose particles because its nucleus contain an excess of internal energy (neutron or proton).
This ultimately implies that, an unstable element is radioactive in nature.
In Science, some examples of an unstable element are:
Polonium is a chemical element with a large, unstable nucleus.
Basically, the most stable isotope of Polonium is Polonium-209, which typically undergoes an alpha decay to form lead-205 and the emission of an alpha particle.
⇒
----> 
In conclusion, we can deduce from the above chemical equation that Polonium is most likely to become stable through an alpha decay.
Read more: brainly.com/question/18214726
Ductility because ductility is the ability to be stretched and be made into wires.
The transitions which fall to the lowest principle position release the greatest energies. In this case, this would be the transition from the 5p to the 3s orbital (a Paschen transition).
Hope this helps!